Cutter bit and carrier therefor



Nov. 18, 1930.

Filed March 8, 1924 Patented Nov. 18, 1930 PATENT OFFICE NI'LS D. LEVIN, OF COLUMBUS, OHIO, ASSIGNOB TO THE JEFFREY MANUFACTURING COMPANY, OF COLUMBUS, OHIO. A CORPORATION 01? OHIO CUTTER BIT AND CARRIER THEREFOR Application filed March 8, 1924. Serial No. 897,789.

The present invention relates to certain new and useful im rovements in cutter bits and carriers there or, adapted to use in coal minin machines for the cuttin of kerfs in the vein preparatory to dislodging the coal.

travels an endless chain equipped with renewable cutter bits adapted to engage the coal to cut it. Although these cutter bits are formed of specially treated high grade tool steel, they soon become dull in service and must frequently be removed from the chain and taken to a blacksmith shop outside to be shar ned and reshaped. After a limited num r of such dressings these bits become too small for further use and the proportion of waste thus resulting far exceeds the proportions consumed in service. Iam aware that numerous devices have been proposed wherein this proportion of waste metal is reduced by the use of relatively small tool steel cutters associated with special holding devices adapted to be attached to the cutter chain. All of these devices, however, with which I am familiar possess certain inherentdefects which it is the object of this invention to overcome.

The especial object of this invention is to provide a cutter bit of im roved design whereby will be eliminated t e blacksmith work entailed in the reshaping and sharpeningof cutter bits and by which the waste of metal will be re need to a negligible minimum.

A further object is to provide improved holding devices for the attachment of my improved cutter bit to the cutter chain.

The means whereby I attain these objects ,are fully set forth in the following specification and illustrated in the accompanying drawings of which- Fig. 1 is a side elevation of a section of chain illustrating the preferred embodiment of my invention.

Fig. 2 is a detail showing of one of the bit supporting links of a chain illustrated in Fig. 1.

Fig. 3 is an end elevation of the link shown in Fig. 2.

Fig. 4 is a detail showing of an improved cutter bit adapted to use with the chain of my invention.

Figs. 5, 6, 7'and 8,, are modified forms of bit supporting links all of which fall within the spirit of my invention.

Like numerals refer to similar parts in the several figures.

In the drawings I have illustrated an improved cutter chain comprising a series of block links 1 and strap links 2 which are joined together by suitable pintles 3 and which are adapted to travel in the guideways of the cutter frame of a coal mining machine in the manner which is well understood in the art.

Formed on each of the block links 1 is an outwardly projecting lug & having a recess wherein is mounted a clamping member 5, and the opposing faces 6 and 7 are shaped to form a re-entrant angle or undercut recess to fit about and securely hold the cutter bit in operative relation with the cutter chain. In order to further secure the bit, the arm 4 may be provided witha recess in its upper face disposed at an angle to the clamping face 7, which recess, as shown in dotted lines in the drawings, receives the triangular rear face of the arm 16, and holds the bit against lateral movement, the opposinglface 6 of the movable clamping member 5 aving a corresponding triangular-shaped recess to receive the arm 18" With this arrangement, the bit is very securely locked against movement in any direction. The lugs 4 of successive block links are offset laterally relative to each other, to cause the cutter bits 8 to travel in laterally spaced paths, as indicated by the dotted line 9 in Fig. 3, to form a. kerf of sufiicient width to afford clearance for the cutter chain and its supporting cutter frame. The clamping member 5 is supported for rocking adjustment about a pivot pin 10, and has a rearwardly extending arm 11 which engages a cam 12 formed integral with the stud 13. The stud 13 is rotatable in a longitudinally extendin aperture of the lug 4, and is held against fimgitudinal displacement by a locking key 14 which engages a circum-- ferential groove in said stud. A square head 15 formed on the stud 13 is adapted to be engaged by a suitable wrench by which the cam 12 may be rotated to rock the clamping member 5 into locked position. The cutter bit 8 is star shaped, having referably four radiating cutting arms 16, 17, 18 and 19, of substantially pyramidal shape, two of the arms, 17 and 18, at least, being clamped by suitable holding devices to secure them in place on the chain. In the present showing three of the arms 16, 17 and 18, are engaged by the clamping surfaces 6 and 7 to hold the fourth arm 19 in coal engaging position upon the cutter chain. As each successive arm becomes dulled by use the bit 8 may be readjusted in the clamping surfaces 6 and 7 to present a new cutting arm until all have become dull. Since each of my improved star shaped bits is the cutting equivalent of four, and contains materially less tool steel than one of the bits heretofore used, it is apparent that their use will efl'ect a material economy in the consumption of tool steel, and since the cutting arms are all formed and sharpened when the bit is manufactured, the necessity for a bit dresser at the mine is eliminated. It will be observed that the arms of the bit 8 are substantially triangular in cross section, so as to give a flat front wall and a triangular rear wall to engage the complementary clamping surfaces on the bit carrying links. In order to make a compact and strong bit, the pyramidal arms are disposed with respect to the body portion 8 and one another, as clearly shown in Figure 4, where the triangular rear wall of the arm overlaps the flat front face of an adjacent arm.

While I have shown, in the present illustration, four cutting arms, and this is a preferable form, it will be understood that the number of arms might be increased or diminished, the only requisite being that there shall be at least two arms which will serve as projections to be engaged by the clamping members to secure the cutter bit in place.

In Fig. 5 there is shown a modification of the block link above described wherein the cam supporting stud 20 extends transversely of the cutter chain. As in the first described link, the cam 21 engages the arm 22 of the clamping member 5, and the square head 23 of the stud 2O aifords means for the rotation of the cam 21 to rock the clamping member 5 into locking position.

In Fig. 6 is disclosed a further modification wherein the arm 24 of the clamping member is engaged by a wedge 25 movement of which rearwardly of the chain tends to deflect the arm 24, and thereby rock the clamping member 5 into locking position.

In Fig. 7 a further modification is presented whereby the clamping member 26 is rigidly attached to a sliding bar 27 adapted to slide longitudinally of the chain. A cam 28 mounted upon the sliding bar 27 engages the rearward surface 29 of the lug 4, and a square head 30 formed on the cam 28 provides means for its rotation to slide the bar 27 rearwardly of the chain and thereby move the clamping member 26 into looking position.

In Fig. 8 is shown a still further modification whereb the clamping member 31 may be drawn into contact with the cutter bit 8 by a bolt 32 extending longitudinally of the block link 4. All of these modifications serve to clamp the cutter bits in operative relation with the cutter chain in substantially the same manner, and it is apparent that still further modification may be made in these parts without departure from the spirit of my invention.

By the above described invention I have provided a renewable cutter bit of convenient and economical design, combined with durable and eflicient means for its attachment to the cutting chain, thereby attaining extreme convenience in operation and economy of manufacture.

What I claim is:-

1. In a coal cutting apparatus, the combination with a cutter chain, of a cutter bit having a plurality of cutting arms adapted to be successively placed in coal cutting position upon the chain, and means upon the chain to en age at least two of said arms to hold the it against bodily displacement and at least one arm in coal cutting position.

2. In a coal cutting apparatus, the combination with a cutter chain, of a cutting bit having a plurality of similar cutting arms adapted to be successively placed in coal cutting position upon the chain, and means upon the chain to engage at least two of said arms to hold the bit against bodily displacement and at least one arm in coal cutting position.

3. In a coal cutting apparatus, the combination with a cutter chain, of a cutter bit having a plurality of radially extending cutting arms adapted to be successively placed in coal cutting position upon the chain, and means upon the chain to engage at least two of said arms to hold the bit against bodily displacement and at least one arm in coal cutting position.

4. In a coal cutting apparatus, the combination with a substantially star shaped cutter bit the arms of which are adapted to be successively placed in coal cutting position upon the chain, and means upon the chain to engage at least two of the arms of the star to hold the bit against bodily displacement and at least one arm in coal cutting position.

5. In a coal cutting apparatus, the combination with a cutter chain having links adapted to support the cutter bits, of a cutter bit having a plurality of radially extend ing arms adapted to be successively placed in coal cutting position upon a bit carrying link of said chain, and clamping members carried by said bit supporting link adapted to engage at least two of the arms of said bit to hold the bit against bodily displacement and at least one arm in coal cutting position.

6. In coal cutting apparatus, the combination of a cutter chain having a bit carryingslink, a cutter bit having a plurality of su tantially radial cutting arms adapted to be successive] used, and opprsed clamping means on sai bit carrying link so disposed as to form with each other an undercut recess to receive at least two of said arms and hold the bit in position.

, successively used, and

7 In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter -bit having a plurality of substantially radial cutting arms adapted to be opposed clamping means on said bit carryin link provided with bit reoeivin seats an so disposed as to form with eacfi other an undercut recess to receive at least two of said arms and hold the bit in position, one of said clamping means engaging a third arm on said bit.

8. In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of substantially radial cutting arms adapted to be successively used, a fixed clamping member havin an undercut recess projecting from said bit carrying link, a movable clamping member having an undercut recess opposed to said fixed member to clamp at least two of said arms and hold the bit in position,

i and means for securing said second clamping member in clamping position.

9. In coal cutting. apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of sul stantially radial cutting arms adapted to be successively used, a fixed clamping member having an undercut recess projecting from said bit carrying link, a movable clamping member having an undercut recess opposed to sa d fixed member to clamp at least two of said arms and hold the bit in position, and means for moving said second clamping member into clamping position.

10. In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of substantially radial cutting arms adapted to be successively used, a fixed clamping member having an undercut recess projecting from said bit carrying link, a movable clamping member having an undercut recess opposed to said fixed member to clamp at least two of said arms and hold the bit in position, and a cam device for moving said second clamping member into clamping position.

11. In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of substantially radial cutting arms adapted to be successively used, a. fixed clamping member having an undercut recess projecting from said bit carrying link, a second clamping member having an undercut recess opposed to said fixed member to clamp at least two of said arms and hold the bit in position movably mounted on said link, and a cam device for moving said second clamping member into clamping position.

12. In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of sub stantially radial cutting arms adapted to be successively used, a fixed clamping member having an undercut recess projecting from said bit carrying link, a second clamping member having an undercut recess oppose to said fixed member to clamp at least two of said arms and hold the bit in position pivotally mounted on said link, and a cam' device for moving said second clamping member into clamping position.

13. In coal cutting apparatus, the combination of a cutter chain having a bit carrying link, a cutter bit having a plurality of sub stantially radial cutting arms adapted to be successively used, a fixed clamping member having an undercut recess projecting from said bit carrying link, a second clampin member having an undercut recess oppose to said fixed member to clamp at least two of said arms and hold the bit in position pivotally mounted on said link and having a cam actuated arm, and a cam device for moving said second clamping member into clamping position.

14. In coal cutting apparatus, the combination of a cutter chain havin a bit carrying link, a cutter bit having a p urality of substantially radial cutting arms adapted to be successively used, a fixed clamping member having an undercut recess projecting from said bit carrying link, a second clamping member having an undercut recess opposed to said fixed member to clamp at least two of said arms and hold the bit in position pivotally mounted in a recess in said link and having a cam actuated arm, and a cam device for moving said second clamping member into clamping position.

15. A bit carrying link for cutter chains having a fixed lug provided with an undercut recess to provide a substantially fiat bit retaining wall for a cutter bit arm, and a substantially triangular recess angularly disposed with respect to said wall to receive a second arm of a cutter bit, and a movable clamping member 0 posed to said fixed clamping member having an inclined wall to III form an undercut recess with a substantially traingular seat in said well to engage a third arm of a cutter bit.

16. A cutter bit having a body portiongmd 5 a plurality of substantlally pyramidal cutting arms, each of said arms having a substantiall flat front face and a substantially V-shape rear face extending from said body portion in a substantially radial direction, the said V- hoped rear portion of each of said arms overlapping the flat front face of the adjacent arm.

In testimony whereof I have hereunto set my hand.

NILS D. LEVIN.

the adjacent am.

In testimony whereof I have hereunto set my hand. m NILS D. LEVIN.

I 7 CERTIFICATE OF CORRECTION. Patent No. 1,782,172. Granted November 18, 1930, to

NILS o. LEVIN. A

It is hereby certified that error appears in the rinted above numbered patent requiring correction as folloo sz Pagz if lifiz a :i itie i the word 'about"- insert the words at least two of the arms of the cutter bit 8' page 2, lines 6 and 7, the words "The cutter bit 8" should be the beginning of a paragraph; page 4, line 2, claim 15, for the misspelled word "traingular" read triangular; and that the said Letters Patent should he read with these Signed and sealed this 27th day of January, A. D. 1931;

M. J. Moore, (Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,782,172. Granted November I8, 1930, to

NILS D. LEVIN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 74, after the word "about' insert the words at least two of the arms of the cutter bit 8; page 2, lines 6 and 7, the words "The cutter bit 8" should be the beginning of a paragraph; page 4, line 2, claim 15. for the misspelled word "traingular" read triangular; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 27th day of January, A. D. 1931.

M. J. Moore, Acting Commissioner of Patents. 

